Preliminary diagnosis would be a 1940 Charles.
The movement is a 15 J 10AX which is consistent with the ones in the database. The case back is marked "Bulova New York. Its got a 10K rolled yellow gold plate bezel with a stainless back.
I hadn't actually realized how few of these there are in the database. Its an interesting one.
Nice one Tom! This is one we don't see very often, I agree it's a Charles.
Interesting the movement appears to be double stamped with an asterix and omega, indicating 1940 and 1941. Based on the double stamp, it's likely a year transition thing, so I'm inclined to date it as a 1940 going with the case serial number. It's possible they started re-stamping movements in late 1940 preparing for the new year and used some in late 1940. Without the 1940 stamp, I would be on the fence as to whether to call it a 1941.
1940 Charles